The EIA, a research and statistical arm of the Department of Energy, issued its final weekly coal production report of 2012 on Friday. That means the final two days of the year still need to be included in the tally.

Mines in the state produced an estimated 398 million tons in 2012, compared to 436 million tons in 2011. Nationwide, coal production dropped about 7 percent, to 1.02 billion tons.

Industry officials say the decrease in production is due to sagging natural gas prices, a mild winter and stricter regulations on coal-burning power plants.